7 research outputs found
Prompt neutrino fluxes in the atmosphere with PROSA parton distribution functions
Effects on atmospheric prompt neutrino fluxes of present uncertainties
affecting the nucleon composition are studied by using the PROSA fit to parton
distribution functions (PDFs). The PROSA fit extends the precision of the PDFs
to low x, which is the kinematic region of relevance for high-energy neutrino
production, by taking into account LHCb data on charm and bottom
hadroproduction. In the range of neutrino energies explored by present Very
Large Volume Neutrino Telescopes, it is found that PDF uncertainties are far
smaller with respect to those due to renormalization and factorization scale
variation and to assumptions on the cosmic ray composition, which at present
dominate and limit our knowledge of prompt neutrino fluxes. A discussion is
presented on how these uncertainties affect the expected number of atmospheric
prompt neutrino events in the analysis of high-energy events characterized by
interaction vertices fully contained within the instrumented volume of the
detector, performed by the IceCube collaboration.Comment: 36 pages, 17 figures, 1 tabl
Impact of heavy-flavour production cross sections measured by the LHCb experiment on parton distribution functions at low x
The impact of recent measurements of heavy-flavour production in deep
inelastic scattering and in collisions on parton distribution
functions is studied in a QCD analysis in the fixed-flavour number scheme at
next-to-leading order. Differential cross sections of charm- and beauty-hadron
production measured by LHCb are used together with inclusive and heavy-flavour
production cross sections in deep inelastic scattering at HERA. The
heavy-flavour data of the LHCb experiment impose additional constraints on the
gluon and the sea-quark distributions at low partonic fractions of the
proton momentum, down to . This kinematic range is
currently not covered by other experimental data in perturbative QCD fits
Prompt neutrino fluxes in the atmosphere with PROSA parton distribution functions
Effects on atmospheric prompt neutrino fluxes of present uncertainties affecting the nucleon composition are studied by using the PROSA fit to parton distribution functions (PDFs). The PROSA fit extends the precision of the PDFs to low x, which is the kinematic region of relevance for high-energy neutrino production, by taking into account LHCb data on charm and bottom hadroproduction. In the range of neutrino energies explored by present Very Large Volume Neutrino Telescopes, it is found that PDF uncertainties are far smaller with respect to those due to renormalization and factorization scale variation and to assumptions on the cosmic ray composition, which at present dominate and limit our knowledge of prompt neutrino fluxes. A discussion is presented on how these uncertainties affect the expected number of atmospheric prompt neutrino events in the analysis of high-energy events characterized by interaction vertices fully contained within the instrumented volume of the detector, performed by the IceCube collaboration
Prompt neutrino fluxes in the atmosphere with PROSA parton distribution functions
Abstract Effects on atmospheric prompt neutrino fluxes of present uncertainties affecting the nucleon composition are studied by using the PROSA fit to parton distribution functions (PDFs). The PROSA fit extends the precision of the PDFs to low x, which is the kinematic region of relevance for high-energy neutrino production, by taking into account LHCb data on charm and bottom hadroproduction collected at the center-of-mass energy of s = 7 TeV. In the range of neutrino energies explored by present Very Large Volume Neutrino Telescopes, it is found that PDF uncertainties are far smaller with respect to those due to renormalization and factorization scale variation and to assumptions on the cosmic ray composition, which at present dominate and limit our knowledge of prompt neutrino fluxes. A discussion is presented on how these uncertainties affect the expected number of atmospheric prompt neutrino events in the analysis of high-energy events characterized by interaction vertices fully contained within the instrumented volume of the detector, performed by the IceCube collaboration
1er colloque international du Labex Futurs Urbains : "Enjeux interdisciplinaires émergents pour comprendre, projeter et fabriquer la ville de demain"
Ce 1er colloque international du labex Futurs Urbains "Enjeux interdisciplinaires émergents pour comprendre, projeter et fabriquer la ville de demain" se déroulera les 16, 17 et 18 janvier 2013 à la Cité Descartes, Champs sur Marne, 77455 Marne la Vallée. Renseignements et inscriptions : http://villes-environnement.fr/fr/appel.html Présentation extraite du site : Le présent colloque international est centré sur ces questions carrefours, que nous voulons identifier et approfondir, autour de qu..
Impact of heavy-flavour production cross sections measured by the LHCb experiment on parton distribution functions at low x
The impact of recent measurements of heavy-flavour production in deep inelastic scattering and in collisions on parton distribution functions is studied in a QCD analysis in the fixed-flavour number scheme at next-to-leading order. Differential cross sections of charm- and beauty-hadron production measured by LHCb are used together with inclusive and heavy-flavour production cross sections in deep inelastic scattering at HERA. The heavy-flavour data of the LHCb experiment impose additional constraints on the gluon and the sea-quark distributions at low partonic fractions of the proton momentum, down to . This kinematic range is currently not covered by other experimental data in perturbative QCD fits